C++ stl pop doesn't return [closed]

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I have experienced, that the stl pop function doesn't return anything.

How can I return the top element of my stack and delete it?

The top function is not a good solution, because it returns only a reference of the top element...

Answer 1

If you don't need the element anymore after popping it just

// use element with
container.top();
// remove it
container.pop();

Otherwise make a copy of the object:

Element e = container.top();
container.pop(); // remove it
// feel free to use e, you made a copy of it

If you need to really delete it manually then you are not using any kind of smart pointer, which moves the problem to another topic.

Answer 2

You should combine member functions top() and pop(). For example

#include <iostream>
#include <stack>

int main()
{
   std::stack<int> s( std::stack<int>::container_type { 1, 2, 3 } );

   while ( !s.empty() )
   {
      int x = s.top();
      s.pop();
      std::cout << x << ' ';
   }
   std::cout << std::endl;
}

The output is

3 2 1

In this example the element that is in the top of the stack is copied in variable x, that is v ariable x will contain a copy of the element.